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Energy losses caused by misalignment in rotating machinery: A theoretical, experimental and industrial approach

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Abstract

This paper deals with one of the most common malfunctions in rotative machines: misalignment. Several studies have shown that misalignment produces at least 30% of the faults caused by vibration. In this work, an analysis of energetic losses generated by misalignment in rotative machines has been carried out, with the main objective of finding a correlation between vibration levels, energy consumptions and different degrees of misalignment. A laboratory test rig has been implemented to carry out experimental tests under different degrees of misalignment. Two industrial cases, one from a mining company and another from a thermoelectric company have been included in this study and two different methodologies were used to analyse the results. A statistical model based in the Response Surface Methodology (RSM) was used for the data analysis of one of the industrial cases. A simplified economical study illustrates the advantages for a company, when a preventive and predictive methodology is implemented, with the objective of reducing the energy consumption and keeping low levels of vibration by means of alignment.
... R OTATING machinery equipment plays an important role in modern industries, such as energy, transportation, and aerospace [1], [2], [3]. Among its key components, rolling bearings have a significant impact on the safety and reliability of rotating machinery [4]. ...
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... Gaberson and Cappillino, (1996) established an experimental program to conduct accurate measurements of the energy lost due to misalignment and unbalance of rotating machinery. Estupiflan et al., (2008) finding a correlation between vibration levels and energy consumptions for different degrees of misalignment. ...
... For example, according to H.A. Gaberson [13], nearly 3% of energy losses are due to misalignment, while the unbalance leads to losses of less than 1%. E. Estupinan et al. [14], presented an analysis of energetic losses generated by misalignment, which was based on vibration measurements. It was proved economically that the implementation of predictive maintenance reduces energy consumption and keeping low levels of vibration. ...
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In this study we present an evaluation of the energy consumption in the case of shaft misalignment. Misalignment is one of the most common defects in rotating machinery that causes noticeable losses of energy. The proposed methodology focuses on finding a correlation between vibration level and energy consumption for different degrees of misalignment. In fact, the monitoring of energy consumption became a necessity for industries for the implementation of the appropriate maintenance strategy. In order to achieve this, vibration analysis is a measurement tool used to detect and diagnose rotating machinery faults, such as misalignment, unbalance and bearing defects. The results of this experimental investigation show that the rate of energy consumption depends highly on the degree of shaft misalignment, especially, in the case of parallel misalignment. Also, vibration analysis has been proven to be an effective tool to early detect misalignment shaft and monitoring electrical energy consumption.
... For example, according to H.A. Gaberson [13], nearly 3% of energy losses are due to misalignment, while the unbalance leads to losses of less than 1%. E. Estupinan et al. [14], presented an analysis of energetic losses generated by misalignment, which was based on vibration measurements. It was proved economically that the implementation of predictive maintenance reduces energy consumption and keeping low levels of vibration. ...
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Full-text available
In this study we present an evaluation of the energy consumption in the case of shaft misalignment. Misalignment is one of the most common defects in rotating machinery that causes noticeable losses of energy. The proposed methodology focuses on finding a correlation between vibration level and energy consumption for different degrees of misalignment. In fact, the monitoring of energy consumption became a necessity for industries for the implementation of the appropriate maintenance strategy. In order to achieve this, vibration analysis is a measurement tool used to detect and diagnose rotating machinery faults, such as misalignment, unbalance and bearing defects. The results of this experimental investigation show that the rate of energy consumption depends highly on the degree of shaft misalignment, especially, in the case of parallel misalignment. Also, vibration analysis has been proven to be an effective tool to early detect misalignment shaft and monitoring electrical energy consumption.
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The primary goal of this book series is to promote research and developmental activities in mechanical engineering. It aims at promoting scientific information exchange among the academicians, researchers, developers, engineers, students, and practitioners working around the world. This book covers the chapters on Advances in Mechanical Engineering.
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Chapter
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The problem of power loss in rotating machinery subjected to the angular misalignment and unbalancing faults are of great importance in relevant industries. Therefore, in this study, evaluation of the power loss and bearing forces of a typical coupling-disk-shaft system with angular misalignment and unbalancing faults is conducted using a novel approach based on the multibody dynamics. In this concern, the flexible coupling is modeled by linear and torsional spring-damper elements. After introducing the model, the kinematic constraints as well as the general form of Euler -Lagrange equations of motion are expressed. Then, the generalized forces are derived in detail. The equations of motion are then solved numerically by the 5th order Runge-Kutta method to evaluate the system power loss. In addition, the effect of angular misalignment and unbalancing faults on the disk displacements as well as the bearing forces are discussed. In the next part of this study, the theoretical results of the power loss are verified experimentally on a faulty simulator system. For measuring the power consumption, a digital power analyzer is used. The results of this research clearly highlight how the power loss is affected by increasing the amount of the system rotational velocity, the angle of misalignment, and the unbalance mass.
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